<!DOCTYPE html>
<style>
#backdrop {
  position: absolute;
  top: 100px;
  left: 100px;
  height: 100px;
  width: 100px;
  background: green;
}
</style>
<body>
Test that ::backdrop inherits from its originating element. The test passes if
there is a green box and no red.
<div id="backdrop"></div>
</body>
